Hamlet does not love Ophelia because all through the play he is playing with her mind witch leads to her insanity. Weather it is using her, telling her she is a "whore" or telling her straight up that he does not love her. Also he does not feel bad or try to comfort her when she finds out he killed her dad and she is upset. All of this makes her go crazy and leads to her suicide.
The first reason Hamlet does not love her is because in the play that she is a slut and that he just plain out does not love her. "Oph. My lord, I have remembrances of yours that I have longed to redeliver. Ham. No, not I."(p.280) In this quote from the play, during a conversation between Ophelia and Hamlet, Ophelia is telling Hamlet she loves him and wants to be with him.
Hamlet doesn't want this.
Secondly Hamlet straight out calls her a slut. "Ham. Get thee to a nunneryÃ¢ÂÂ¦" (p.282) In these days saying this meant that she was a whore, and that he didn't want to be with her anymore. He didn't want love, marriage, or breeding.
Next, later on in the play, Hamlet tells her straight up that he wants to use her. This takes place during the play within the play. Hamlet says, "Ham. Lady, shall I lie in your lap? Oph. No, my lord. Ham. I mean, my head upon your lap. Oph. Ay, my lord."(p.294) He says this just moments after he tells her he doesn't want anything to do with her, so obviously he is just trying to use her, therefore doesn't really love her.
Lastly, Hamlet doesn't really love her because after causing her all these problems and killing her dad, weather he is crazy or not, does not take any responsibility or try to comfort her at all. He just avoids that whole situation altogether. This happens all throughout Act III. Hamlet just ignores all the pain he caused her witch eventually leads her to insanity and suicide.
In conclusion, after knowing all this, there is no possible way that Hamlet could have really loved Ophelia. If he did he would have stuck with her after he took her virginity, comforted her when he accidentally killed her father, and would have tried to make things work between the two of this. There is plenty of evidence in that play that he did not make any effort at all, from Act II till her death to try to "love" her.